"Some of them tried Mastodon early and gave up quickly."

A perception is that #Mastodon is more fractured ... that communities haven't matured to the extent that enables a less intentional user to sense their 'connectedness.'

Example: Here, my feed is much more filtered here than it was in the #birdverse.

That's either a good thing or leaves one with a sense of isolation.

Not seeing the yuck, affects some folk's confidence - "What am I missing." So they wander back to peek, and stay.

$.02